1. Field of the Invention
The present invention relates before all to a cutter assembly for slitting of material coils to one or several strips of desired width or for edge-trimming. The slitting operation is performed between revolving annular cutters and spacers. The strip for slitting is preferably made of steel, aluminum or plastics. The invention is directed to rapidly changing of cutters and spacers on the arbors of the slitter also storage them within a narrow place in connection to the slitter.
The present invention relates primarily to a device to store and move cutters and spacers for the cutter assembly for a slitter mill for slitting or cutting coils of materials. The coils can be cut to a strip or strips of desired width. Additionally, the cutter assembly can be used for trimming the edges of coils of material. The present invention relates to a rapid changing of the cutters and spacers of the cutting assembly, and the storage of the cutters and spacers.
2. Background Information
Longitudinal slitting of coils of large width is preferably performed in a cutter assembling means or a slitter between two cutting rings or annular cutters, situated above each other and overlapping. The strip is directed in between two horizontal arbors, mutually parallel disposed above each other and equipped with dish shaped cutters and intermediate spacers. The spacers are for getting desired width of the slit strip. The two arbors are in the ends mounted in bearings in two frame portions. The frame portions are often disposed on the same base plate.
To explain, the lengthwise (longitudinal) slitting of wide coils of material can preferably be performed by a slitter, or cutter, or cutter assembly, or slitter mill which contains two annular cutters. The annular cutters can be positioned so that they are disposed substantially one above the other. Also the cutting surfaces of the cutters can at least partially overlap.
The strip to be slit can be directed between two horizontal arbors, which two horizontal arbors can be substantially parallel to each other with one disposed substantially directly above the other. The arbors can be equipped with one or more dish or disc shaped cutters and can also be equipped with one or more spacers. The spacers can be designed and positioned to separate the cutters so as to cut the strips or slits of material to the desired width. The arbors can be supported by a frame. The frame can have two substantially vertical portions, which vertical portions can support the arbors. The vertical portions can also contain bearings to support the arbors. The vertical portions can also be supported by a common base plate.
When changing for example of the width and/thickness of the desired strips, changing the material, and depending on the wearing out of the cutters on the arbors, the tool set must be reassembled and new be assembled. The lists of orders of course also determine how often the tool sets must be changed. New slitters have high output, often with a slitting speed up to 600 meter per minute or sometimes higher. The capacity of the slitter assembling means highly depends on the time for reassembling and assembling of the tool sets.
Several situations can result in the need for disassembly and removal of the spacer and slitter assembly and then assembly and replacement of a different slitter assembly. An obvious example is when there is a desire to cut different size strips. It can then be necessary to replace the cutter assembly with cutters and spacers properly aligned for the new product size. Similarly, if the material to be cut is different, different cutters may be needed to properly cut that material. Also, the spacers, and particularly the cutters, can become worn and replacement can then be required to maintain proper cutting tolerances. The list of orders or production requirements can also affect the need to replace the cutters and spacers. With slitter assemblies often capable of outputs in excess of about 600 meters per minute, the time required for removal, assembly and installation of the cutter and spacer sets can greatly affect the overall output of the system.
Reassembling and assembling of tool sets makes now preferably in two different ways. One way is to move the whole package of frame portions including the arbors and the cutters and spacers to a separate place and replace the tool sets with new. Sometimes it is possible to make some changes of the tools and direct replace the tool set in the slitter. The other way is that one of the frame portions is reassembled in a well known way to lay one end of the arbor free and then reassembling and assembling the tool sets when the arbors are still in place. Such a slitter is described among others in EP 0444047 and EP 0783942.
The last mentioned way above is to be preferred most of the users of slitter and says depends on that the means are cheaper. Many users also say that this way is faster if the tool sets are changed in an advanced way.
Different methods can be used for the assembly and installation of cutter or tool sets. One option requires the removal of the entire frame portion, along with the associated arbors and tool sets from the slitter machine. Once removed, the tool sets can be accessed for the replacement of the cutters and spacers. The frame and associated tool sets can then be replaced into the slitter machinery. While generally the entire tool set is changed, in some cases it may be possible to change some portion of the tool sets while still installed in the slitter. Another option for the removal of the tool sets calls for the removal of just one of the frame portions. Upon removal of one of the frame portions, the tool sets can be removed, reassembled and reinstalled while the arbors remain in place, held by the other frame portion. The removed frame portion can then be reinstalled and the slitter can then once again be ready for operation. The latter method of replacement of the cutters and spacers is generally preferred, as it is commonly believed to be more time and cost efficient to replace the slitters in this manner.
The easiest way of changing tool sets is to loosen the cutters and spacers from the arbors and one after one by hand or with help of somewhat common equipment reassemble the tools and then assemble new cutters and spacers.
In the patent EP 0783942 is described a set-up device to facility change the whole tool set. The set-up device is built up of an upright, equipped with in pairs above each other situated bars similar to the arbors on the slitter. The set-up device will preferably at least be equipped with four in pairs placed bars oriented in different directions. The set-up device is adapted to be moved between a mounting station and a docking station at the mill stand. The pairs of bars of the set-up device are docked with the arbor pair. For this purpose the end wall of the mill stands can be opened. The used tool set is pushed over to the bars. New bars on the set-up device are now docked with the ends of the arbors and newly built up tool sets are pushed over to the arbors. The movements of the tool sets on the bars and arbors are made by pushers on the set-up device or the slitting stand or on both.
In other words, the patent EP 0783942 describes a device to facilitate the removal and replacement of an entire tool set. Projections similar to the arbors on a slitter are disposed on an upright portion. The projections can be substantially parallel to one another. There can preferably be at least two such pairs of projections on the device, with each pair extending in a different direction. The device can be designed to move between a first position and a second position. In the first position the device stores the arbor sets. In the second, docked position, a pair of projections can dock with the arbors of the cutter. Upon docking, the used tool set can then be pushed onto the bars. The device can be rotated so another pair of bars, carrying the replacement tool set, can be docked with the arbors, and the new tool set can be transferred to the arbors. The device for removal and replacement and or/the slitter itself, can be equipped with pushing mechanisms to push the old tool sets off of the arbors and the new tool sets onto the arbors.
The storage of the cutters and spacers is made by stocking them in a place near the slitting stand or the slitting stands if more than one slitting stand are used. The storage place can be extensive. The best way of building up the space between two cutters is to pair together spacers of different thicknesses to one unit in order to gets the desired widths of the slitted coils. These spacer sometimes can have up to one hundred different thicknesses or even more. It is also necessary to magazine many different cutters. Moving the tools between the stockage and the stand is executed in the simplest way by hand. Equipment, for example robots, can sometimes be used, As the cutters and spacers often magazines on a horizontal floor the extend of the storage will be large. Being also in mind that each tool set can be built up by up to 30 parts and the robot is able to move only one part each time the moving time will be extensive.
In other words, the cutters and spacers can be stored in an area near the slitting machine. Due to the number of cutters and spacers involved, and the number of combinations of cutters and spacers for all of the different materials and sizes of strips to be cut, an extensive storage area can be necessary. For example, it may be necessary to have more than 100 different sizes of spacers available to set up the tool sets for the correct width of material to be cut. Also, each tool set can possibly include 30 or more cutters and spacers. Due to the number of components involved, an extensive amount of time can be required to correctly assemble all of the stored tool sets.